Some stuff for you to read:
https://aos-tactics.com
https://1d4chan.org/wiki/Age_of_Sigmar/Tactics
Seeing the armies you face you need some more advanced armylist setup.
Your models are all good units, but what you miss is a punchline. Some really heavy hitters. No worries though that can be countered with the stuff you are playing just make sure you know that that is a weakness and don't just move up to
Try to think consistency. What are you facing, and how are you going to do something about it.
Something like the terrorgheist manfred thing, I would try to keep it at bay with a list that has summoning pts, summon some flamers and blow the hell out of that terrorgheist, finish it with a charge of some knights with glaives. Be sure to have a second unit of knights waiting in support for the turn after if something goes wrong.
Ask your opponents armylist and keep it at hand. It is a good way to keep track on how many pts he has invested in something.
Try to divide your opponents army, and try to keep your army together. If you can face 600 pts of his with 1000 pts of yours and you get to choose were to strike first, you are gonna get out on top.
Like the terrorgheist is something around 400 pts. Almost anything it touches and attacks first is going to be very dead, so be sure to attack it first with a hard hitting unit. Like 5 knights with Glaives (always give knights glaives and always be sure they are the one that charge and hit first).maybe Charge in a second unit like a chariot so that the terrorgheist needs to retaliate on that unit and not on the knights.
Slaves to darkness is about well timed attacks, and refraining from just going forward with everything, getting charged and wiped out. Your units are expensive and in
AOS any unit can be gone after one charge or shooting face. You lack shooting yourself which is your weakness. This can be solved with adding tzeentch though.
At 1000 pts I usually play (rather competitively without going cheese)
5 knights with glaives
5 knights with glaives
10 warriors
1 chaos lord on foot
1 (socerer)Lord on manticore (either one)
Godsworn champions of ruin
All mark of slaanesh for run and charge. This is a strong, fast and hardhitting list that should be played guerilla style.
At 1500 more tzeentchy (what you are trying to do):
Depending on your houserules this is a format where you need 3 battleline. A lot of clubs limit this to 2. if to put the horrors in reserve pts
put the herald,and flamers in reserves (or put one unit of flamers already on the board)
Proxy warriors as marauders, Proxy a prince as the
LoC. and playtest.
take all your summonable stuff just in case.
Be sure to read the links above there is an article on how to use summoning effectively.
This list will give serious trouble to both lists you have faced but mostly requires good positioning and shooting the right targets. Weakening him down and then mop up.
At 2000 pts add in more heavy hitters (like the knights) they will be a tremendous help, or even a ruinbringer warband next to a
LOC and summon pts.
Allegiance: Chaos
Leaders
Herald Of Tzeentch On Disc (120)
- Staff of Change
Lord Of Change (300)
- General
Chaos Sorcerer Lord (140)
- Runestaff
Units
10 x Pink Horrors Of Tzeentch (140)
3 x Flamers Of Tzeentch (200)
3 x Flamers Of Tzeentch (200)
10 x Chaos Marauders (60)
- Axes
- Mark of Chaos : Tzeentch
10 x Chaos Marauders (60)
- Axes
- Mark of Chaos : Tzeentch
5 x Chaos Knights (200)
- glaives
- Mark of Chaos : Tzeentch
1 x Chaos Chariots (80)
- Greatblades
Total: 1500/1500
Leaders: 3/6
Battlelines: 4 (3+)
Behemoths: 1/4
Artillery: 0/4